TNOWAVE and the Method of Characteristics

TNOWAVE was developed by TNO, the Dutch research organisation. It is different from the Smith/TTI/WEAP wave equation programs in that it uses the method of characteristics to analyse wave propagation in piles.

Documents about TNOWAVE

Investigation of the Effectiveness of a Hammer Blow in Pile Driving

V.G. Esipenko

Although not directly related to the TNO wave equation program, this paper describes analysis of the hammer blow on a pile using the method of characteristics, which is the same method that TNOWAVE uses. It is also, to this webmaster’s knowledge, the only paper from the Soviet era which discusses the wave equation as applied to piling (most Soviet analyses, both for impact and vibratory driving, assumed the pile was a rigid mass.)

Thirty Years of Experience with the Wave Equation Solution Based on the Method of Characteristics

Peter Middendorp, Profound BV
Gerald E.H. Verbeek, VMS-Profound
2005

This paper will describe a brief history of the method of characteristics as an accurate solution of the wave equation, and the authors’ experiences with the method of characteristics over a period of 30 years. As a result of the offshore pile driving activities associated with the development of the North Sea oil fields in the 1970’s, two Dutch companies initiated extensive efforts to research the dynamic behavior of soil during driving as well as to extend the method of characteristics with a straightforward theoretical solution for the shaft friction along the pile. The Dutch governmental research institute TNO started the development of the wave equation program TNOWAVE in the late 1970’s based on this extended method of characteristics with the theoretical solution for shaft friction. Today the program has a worldwide application in the field of pile testing. This paper will describe its development and application over time and its relation to today’s applications for drive-ability studies for impact hammers (PDPWAVE) and vibratory hammers (VDPWAVE), signal matching for Dynamic Load Testing (DLTWAVE), Pile Integrity Testing signal matching (SITWAVE) and Statnamic simulation (STNWAVE). The paper will then focus on Sonic Integrity Testing signal matching, and indicate some areas where developments are required to enhance this type of testing.